Planetary Names: Planet and Satellite Names and Discoverers International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN) Planetary Names: Planet and Satellite Names and Discoverers Home Named Mercurius by the Romans because it appears to move so swiftly. Discoverer Venus Roman name for the goddess of love. This planet was considered to be the brightest and most beautiful planet or star in the heavens. Other civilizations have named it for their god or goddess of love/war. Discoverer Earth The name Earth comes from the Indo-European base 'er,'which produced the Germanic noun 'ertho,' and ultimately German 'erde,' Dutch 'aarde,' Scandinavian 'jord,' and English 'earth.' Related forms include Greek 'eraze,' meaning 'on the ground,' and Welsh 'erw,' meaning 'a piece of land.' Earth I (Moon) Every civilization has had a name for the satellite of Earth that is known, in English, as the Moon. The Moon is known as Luna in Italian, Latin, and Spanish, as Lune in French, as Mond in German, and as Selene in Greek.

Martian System The names of the moons of Mars and the English translations of the names were specifically proposed by their discoverer, Asaph Hall, and as such, they have been accepted and retained under the current IAU nomenclature. Body Discoverer Mars Named by the Romans for their god of war because of its red, bloodlike color. Other civilizations also named this planet from this attribute; for example, the Egyptians named it "Her Desher," meaning "the red one." Mars I (Phobos) Inner satellite of Mars. Named for one of the horses that drew Mars' chariot; also called an "attendant" or "son" of Mars, according to chapter 15, line 119 of Homer's "Iliad." This Greek word means "flight." August 17, 1877 A. Hall Mars II (Deimos) This outer Martian satellite was named for one of the horses that drew Mars' chariot; also called an "attendant" or "son" of Mars, according to chapter 15, line 119 of Homer's "Iliad." Deimos means "fear" in Greek.

August 11, 1877 Selected Asteroids (of the Main Belt) and their Satellites Body Named for the Greek god of love. August 13, 1898 Named for a resort on the Crimean Peninsula. July 30, 1916 G. Neujmin (243) Ida Named for a nymph who raised the infant Zeus. Ida is also the name of a mountain on the island of Crete, the location of the cave where Zeus was reared. September 29, 1884 J. Palisa (243) Ida I (Dactyl) Named for a group of mythological beings who lived on Mount Ida, where the infant Zeus was hidden and raised (according to some accounts) by the nymph Ida. August 28, 1993 Galileo imaging and infrared science teams. (253) Mathilde The name was suggested by a staff member of the Paris Observatory who first computed an orbit for Mathilde. The name is thought to honor the wife of the vice director of the Paris Observatory at that time. November 12, 1885 J.

Palisa (22) Kalliope I (Linus) Satellite of (22) Kalliope. In various accounts of Greek mythology, Linus is considered to be the son of the Muse Kalliope and the inventor of melody and rhythm. August 29 and September 2, 2001 Mauna Kea J.-L. Margot, M.E. Brown, W.J. Merline, F. Menard, L. Close, C. Dumas, C.R. Chapman, and D.C. Slater (45) Eugenia I (Petit-Prince) Satellite of (45) Eugenia. The Little Prince, Napolean-Eugene-Louis-Jean-Joseph Bonaparte (1856-1879), was the son of Eugenia de Montijo de Guzm\'an and Napoleon III. November 1, 1998 Mauna Kea W.J. Merline, L. Close, C. Dumas, C.R. Chapman, F. Roddier, F. Menard, D.C. Slater, G. Duvert, C. Shelton, and T.

Morgan Jovian System Satellites in the Jovian system are named for Zeus/Jupiter's lovers and descendants. Names of outer satellites with a prograde orbit generally end with the letter "a" (although an "o" ending has been reserved for some unusual cases), and names of satellites with a retrograde orbit end with an "e." Body Discoverer Jupiter The largest and most massive of the planets was named Zeus by the Greeks and Jupiter by the Romans; he was the most important deity in both pantheons. Jupiter I (Io) Io, the daughter of Inachus, was changed by Jupiter into a cow to protect her from Hera's jealous wrath. But Hera recognized Io and sent a gadfly to torment her. Io, maddened by the fly, wandered throughout the Mediterranean region.

January 8, 1610 Padua Galileo (Simon Marius probably made an independent discovery of the Galilean satellites at about the same time that Galileo did, and he may have unwittingly sighted them up to a month earlier, but the priority must go to Galileo because he published his discovery first.) Jupiter II (Europa) Beautiful daughter of Agenor, king of Tyre, she was seduced by Jupiter, who had assumed the shape of a white bull. When Europa climbed on his back he swam with her to Crete, where she bore several children, including Minos. January 8, 1610 Galileo (who evidently observed the combined image of Io and Europa the previous night) Jupiter III (Ganymede) Beautiful young boy who was carried to Olympus by Jupiter disguised as an eagle. Ganymede then became the cupbearer of the Olympian gods. January 7, 1610 Galileo Jupiter IV (Callisto) Beautiful daughter of Lycaon, she was seduced by Jupiter, who changed her into a bear to protect her from Hera's jealousy.

January 7, 1610 Galileo Jupiter V (Amalthea) A naiad who nursed the new-born Jupiter. She had as a favorite animal a goat which is said by some authors to have nourished Jupiter. The name was suggested by Flammarion. September 9, 1892 A Rhodian nymph who bore three sons of Zeus. December 4, 1904 C.D. Perrine Jupiter VII (Elara) Daughter of King Orchomenus, a paramour of Zeus, and by him the mother of the giant Tityus. January 3, 1905 C.D. Perrine Jupiter VIII (Pasiphae) Wife of Minos, king of Crete. Zeus made approaches to her as a bull (taurus). She then gave birth to the Minotaur. (Spelling changed from Pasiphaë to Pasiphae July 2009.) January 27, 1908 P.J. Melotte Jupiter IX (Sinope) Daughter of the river god Asopus. Zeus desired to make love to her.

Instead of this he granted perpetual virginity, after he had been deceived by his own promises. (In the same way, she also fooled Apollo.) July 21, 1914 S.B. Nicholson Jupiter X (Lysithea) Daughter of Kadmos, also named Semele, mother of Dionysos by Zeus. According to others, she was the daughter of Evenus and mother of Helenus by Jupiter. July 6, 1938 Daughter of the river god Achelous and stepdaughter of Zeus. October 19, 1999 J.V. Scotti, T.B. Spahr, R.S. McMillan, J.A. Larson, J. Montani, A.E. Gleason, and T. Gehrels Jupiter XVIII (Themisto) Daughter of the Arcadian river god Inachus, mother of Ister by Zeus. September 30, 1975, rediscovered November 21, 2000 Palomar, rediscovered at Mauna Kea C.T. Kowal and E. Roemer (1975), and S.S. Sheppard, D.C.

Jewitt, Y.R. Fernandez, G. Magnier, M. Holman, B.G. Marsden, and G.V. Williams (2000). Jupiter XIX (Megaclite) Daughter of Macareus, who with Zeus gave birth to Thebe and Locrus. November 25, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XX (Taygete) Daughter of Atlas, one of the Pleiades, mother of Lakedaimon by Zeus. November 25, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXI (Chaldene) Bore the son Solymos with Zeus. November 26, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXII (Harpalyke) Daughter and wife of Clymenus.

In revenge for this incestuous relationship, she killed the son she bore him, cooked the corpse, and served it to Clymenus. She was transformed into the night bird called Chalkis, and Clymenus hanged himself. Some say that she was transformed into that bird because she had intercourse with Zeus. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXIII (Kalyke) Nymph who bore the handsome son Endymion with Zeus. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXIV (Iocaste) Wife of Laius, King of Thebes, and mother of Oedipus. After Laius was killed, Iocaste unknowingly married her own son Oedipus. When she learned that her husband was her son, she killed herself. Some say she was the mother of Agamedes by Zeus. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R.

Fernandez, and G. Magnier Jupiter XXV (Erinome) Daughter of Celes, compelled by Venus to fall in love with Jupiter. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXVI (Isonoe) A Danaid, bore with Zeus the son Orchomenos. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXVII (Praxidike) Goddess of punishment, mother of Klesios by Zeus. November 23, 2000 S.S. Sheppard, D.C. Jewitt, Y.R. Fernandez, and G. Magnier Jupiter XXVIII (Autonoe) Mother of the Graces by Zeus according to some authors. December 10, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXIX (Thyone) Semele, mother of Dionysos by Zeus.

She received the name of Thyone in Hades by Dionysos before he ascended up with her from there to heaven. December 11, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXX (Hermippe) Consort of Zeus and mother of Orchomenos by him. December 9, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXI (Aitne) A Sicilian nymph, conquest of Zeus. December 9, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXII (Eurydome) Mother of the Graces by Zeus, according to some authors. (Source: Cornutus: Theologiae Graecae compendium 15) December 9, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXIII (Euanthe) The mother of the Graces by Zeus, according to some authors. December 11, 2001 S.S. Sheppard, D.C.

Jewitt and J. Kleyna Jupiter XXXIV (Euporie) One of the Horae, a daughter of Zeus and Themis. December 11, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXV (Orthosie) One of the Horae, a daughter of Zeus and Themis. December 11, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXVI (Sponde) One of the Horae (Seasons), daughter of Zeus. December 9, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXVII (Kale) One of the Graces, a daughter of Zeus, husband of Hephaistos. December 9, 2001 S.S. Sheppard, D.C. Jewitt and J. Kleyna Jupiter XXXVIII (Pasithee) One of the Graces, a daughter of Zeus. December 11, 2001 S.S. Sheppard, D.C. Jewitt and J.

Kleyna Jupiter XXXIX (Hegemone) One of the Graces, a daughter of Zeus. February 8, 2003 Discoverer Saturn Roman name for the Greek Cronos, father of Zeus/Jupiter. Other civilizations have given different names to Saturn, which is the farthest planet from Earth that can be observed by the naked human eye. Most of its satellites were named for Titans who, according to Greek mythology, were brothers and sisters of Saturn. Saturn I (Mimas) Named by Herschel's son John in the early 19th century for a Giant felled by Hephaestus (or Ares) in the war between the Titans and Olympian gods. July 18, 1789 W. Herschel Saturn II (Enceladus) Named by Herschel's son John for the Giant Enceladus. Enceladus was crushed by Athene in the battle between the Olympian gods and the Titans. Earth piled on top of him became the island of Sicily. August 28, 1789 W.

Herschel Saturn III (Tethys) Cassini wished to name Tethys and the other three satellites that he discovered (Dione, Rhea, and Iapetus) for Louis XIV. However, the names used today for these satellites were applied in the early 19th century by John Herschel, who named them for Titans and Titanesses, brothers and sisters of Saturn. Tethys was the wife of Oceanus and mother of all rivers and Oceanids. March 21, 1684 Named by Pickering for one of the Titanesses. August 16, 1898 W.H. Pickering Saturn X (Janus) First reported (though with an incorrect orbital period) and named by A. Dollfus from observations in Dec. 1966, this satellite was finally confirmed in 1980. It was proven to have a twin, Epimetheus, sharing the same orbit but never actually meeting. It is named for the Roman god of the beginning. The two-faced god could look forward and backward at the same time.

December 15, 1966 (Dollfus), February 19, 1980 (Pascu) Pic du Midi (Dollfus), Washington (Pascu) A. Dollfus (1966), D. Pascu (1980) Saturn XI (Epimetheus) First suspected by J. Fountain and S. Larson as confusing the detection of Janus. They assigned the correct orbital period, and the satellite was finally confirmed in 1980. Named for the son of the Titan Iapetus. In contrast with his far-sighted brother Prometheus, he "subsequently realized" that he was in the wrong. 1977 (Fountain and Larson), February 26, 1980 (Cruikshank) Tucson (Fountain and Larson), Mauna Kea (Cruikshank) J. Fountain and S. Larson (1977), D. Cruikshank (1980) Saturn XII (Helene) A granddaughter of Kronos, for her beauty she triggered off the Trojan War.

March 1, 1980 P. Laques and J. Lecacheux Saturn XIII (Telesto) Daughter of the Titans Oceanus and Tethys. April 8, 1980 B.A. Smith, H. Reitsema, S.M. Larson, and J. Fountain Saturn XIV (Calypso) Daughter of the Titans Oceanus and Tethys and paramour of Odysseus. March 13, 1980 D. Pascu, P.K. Seidelmann, W. Baum, and D. Currie Saturn XV (Atlas) A Titan; he held the heavens on his shoulders. October 1980 Voyager Science Team Saturn XVI (Prometheus) Son of the Titan Iapetus, brother of Atlas and Epimetheus, he gave many gifts to humanity, including fire. October 1980 Voyager Science Team Saturn XVII (Pandora) Made of clay by Hephaestus at the request of Zeus. She married Epimetheus and opened the box that loosed a host of plagues upon humanity.

October 1980 Voyager Science Team Saturn XVIII (Pan) Greek god of pastoralism, he was half goat and half human. Son of Hermes, brother of Daphnis, and a descendant of the Titans. Discovered orbiting in the Encke division in Saturn's A ring. 1990 Ymir is the primordial Norse giant and the progenitor of the race of frost giants. August 7, 2000 La Silla B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XX (Paaliaq) Named for an Inuit giant. August 7, 2000 La Silla B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXI (Tarvos) Named for a Gallic giant. September 23, 2000 Mauna Kea B. Gladman, J.

Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXII (Ijiraq) Named for an Inuit giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXIII (Suttungr) Named for a Norse giant who kindled flames that destroyed the world. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXIV (Kiviuq) Named for an Inuit giant. August 7, 2000 La Silla B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M.

Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXV (Mundilfari) Named for an Norse giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXVI (Albiorix) Named for a Gallic giant who was considered to be the king of the world. November 9, 2000 Named for a Norse giantess. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXVIII (Erriapus) Named for a Gallic giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H.

Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXIX (Siarnaq) Named for an Inuit giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXX (Thrymr) Named for a Norse giant. September 23, 2000 Mauna Kea B. Gladman, J. Kavelaars, J.-M. Petit, H. Scholl, M. Holman, B.G. Marsden, P. Nicholson and J.A. Burns Saturn XXXI (Narvi) Named for a Norse giant. February 5, 2003 S.S. Sheppard, D.C. Jewitt, and J. Kleyna Saturn XXXII (Methone) One of the Alkyonides, the seven beautiful daughters of the Giant Alkyoneos. June 1, 2004 S.

Sheppard, D.C. Jewitt, J. Kleyna Saturn XXXVIII (Bergelmir) Norse frost giant, son of Ymir and one of the Hrimthursar, one of only two members of the frost giant race to escape being drowned in Ymir's blood. December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XXXIX (Bestla) Norse primeval goddess, mother of deities, daughter of the giant Bolthorn. December 13, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XL (Farbauti) Norse storm giant, father of Loki. December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XLI (Fenrir) Norse monstrous wolf, son of Loki and the giantess Angurboda, father of Hati and Skoll. December 13, 2004 S. Sheppard, D.C. Jewitt, J.

Kleyna Saturn XLII (Fornjot) Early Norse storm giant, father of Aegir, Kari, and Loge. December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XLIII (Hati) Gigantic Norse wolf, twin of Skoll. December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XLIV (Hyrrokkin) Norse giantess who launched Balder's funeral ship. (Spelling changed from Hyrokkin.) December 12, 2004 S. Sheppard, D.C. Jewitt, J. Kleyna Saturn XLV (Kari) Named for the grotesque, brutish slave in Shakespeare's "The Tempest." September 6, 1997 B. Gladman, P. Nicholson, J.A. Burns and J. Kavelaars Uranus XVII (Sycorax) Named for Caliban's mother in Shakespeare's "The Tempest." September 6, 1997 P. Nicholson, B.

Gladman, J. Burns and J. Kavelaars Uranus XVIII (Prospero) Named for the rightful Duke of Milan in "The Tempest." July 18, 1999 M. Holman, J. Kavelaars, B. Gladman, J.-M. Petit, and H. Scholl Uranus XIX (Setebos) Setebos was a new-world (South American) deity's name that Shakespeare popularized as Sycorax's god in "The Tempest." July 18, 1999 J. Kavelaars, B. Gladman, M. Holman, J.-M. Petit, and H. Scholl Uranus XX (Stephano) Named for a drunken butler in "The Tempest." July 18, 1999 B. Gladman, M. Holman, J. Kavelaars, J.-M. Petit, and H. Scholl Uranus XXI (Trinculo) A jester in Shakespeare's "The Tempest." August 13, 2001 M. Holman, J.J.

Kavelaars and D. Milisavljevic Uranus XXII (Francisco) A lord in "The Tempest." August 13, 2001 J. Kavelaars, M. Holman, D. Milisavljevic, and T. Grav Uranus XXIII (Margaret) A gentlewoman attending on Hero from "Much Ado About Nothing." August 29, 2003 Discoverer Neptune Neptune was "predicted" by John Couch Adams and Urbain Le Verrier who, independently, were able to account for the irregularities in the motion of Uranus by correctly predicting the orbital elements of a trans- Uranian body. Using the predicted parameters of Le Verrier (Adams never published his predictions), Johann Galle observed the planet in 1846. Galle wanted to name the planet for Le Verrier, but that was not acceptable to the international astronomical community. Instead, this planet is named for the Roman god of the sea. September 23, 1846 J.G. Galle Neptune I (Triton) Triton is named for the sea-god son of Poseidon (Neptune) and Amphitrite.

The first suggestion of the name Triton has been attributed to the French astronomer Camille Flammarion. October 10, 1846 W. Lassell Neptune II (Nereid) The Nereids were the fifty daughters of the sea god Nereus and Doris and were attendants of Poseidon (Neptune). May 1, 1949 G.P. Kuiper Neptune III (Naiad) The name of a group of Greek water nymphs who were guardians of lakes, fountains, springs, and rivers. August 1989 One of the Nereids, the fifty daughters of Nereus and Doris. August 14, 2002 M. Holman, J. Kavelaars, T. Grav, W. Fraser, and D. Milisavljevic Neptune X (Psamathe) One of the Nereids, lover of Aeacus and mother of Phocus. August 29, 2003 S.S. Sheppard, D.C. Jewitt, and J.

Kleyna Neptune XI (Sao) One of the Nereids, the fifty daughters of Nereus and Doris. August 14, 2002 T. Grav, M. Holman, J. Kavelaars, W. Fraser, and D. Milisavljevic Neptune XII (Laomedeia) One of the Nereids, the fifty daughters of Nereus and Doris. August 13, 2002 J. Kavelaars, M. Holman, T. Grav, W. Fraser, and D. Milisavljevic Neptune XIII (Neso) One of the Nereids, the fifty daughters of Nereus and Doris. August 14, 2002 Discoverer (134340) Pluto Pluto was discovered at Lowell Observatory in Flagstaff, AZ during a systematic search for a trans-Neptune planet predicted by Percival Lowell and William H. Pickering. Named after the Roman god of the underworld who was able to render himself invisible. January 23, 1930 C.W.

Tombaugh (134340) Pluto I (Charon) Named after the Greek mythological boatman who ferried souls across the river Styx to Pluto for judgement. April 13, 1978 J.W. Christy (134340) Pluto II (Nix) Goddess of darkness and night, mother of Charon. (Nix is the Egyptian spelling of the Greek name Nyx.) May 15, 2005 Hubble Space Telescope H.A. Weaver, S.A. Stern, M.J. Mutchler, A.J. Steffl, M.W. Buie, W.J. Merline, J.R. Spencer, E.F. Young, and L.A. Young (134340) Pluto III (Hydra) In Greek mythology, terrifying monster with the body of a serpent and nine heads that guarded the underworld. May 15, 2005 Hubble Space Telescope H.A. Weaver, S.A. Stern, M.J. Mutchler, A.J. Steffl, M.W. Buie, W.J. Merline, J.R. Spencer, E.F.

Young, and L.A. Young (134340) Pluto IV (Kerberos) In Greek mythology, the many-headed dog that guarded the entrance to the underworld. June 28, 2011 M.R. Showalter, D.P. Hamilton, S.A. Stern, H.A. Weaver, A.J. Steffl, and L.A. Young (134340) Pluto V (Styx) Ariel Ariel Ariel ("AIR ee el") is the twelfth of Uranus 's known satellites: orbit : 190,930 km from Uranus diameter : 1158 km mass : 1.27e21 kg Ariel is a mischievous airy spirit in Shakespeare's The Tempest. Discovered by Lassell in 1851. Ariel and Titania appear quite similar though Titania is 35% larger. All of Uranus' large moons are a mixture of about 40-50% water ice with the rest rock, a somewhat larger fraction of rock than Saturn 's large moons such as Rhea .

Ariel's surface is a mixture of cratered terrain and systems of interconnected valleys hundreds of kilometers long (left, above) and more than 10 km deep. This is similar to, but much larger and more extensive than the situation on Titania. Some of the craters appear to be half-submerged. Ariel's surface is clearly relatively young (though older than some such as Enceladus ); obviously some sort of resurfacing processes have been at work. Some ridges in the middle of the valleys are interpreted as upwellings of ice. Ariel may have been hot inside long ago, but it's cold now. Perhaps the valleys are cracks which formed when Ariel froze. It is actually possible to see Uranus's 4 largest moons with an amateur telescope. But it takes a very dark sky and at least a 12 inch (30 cm) aperture. More about Ariel Ariel | Article about Ariel by The Free Dictionary Ariel | Article about Ariel by The Free Dictionary Also found in: Dictionary , Acronyms , Wikipedia . Ariel (ā`rēĕl), in the Bible, aide of Ezra.

In two other passages AV calls them "lionlike men" ("two ariels of Moab" in RV). Nothing is known of them. Ariel is also used as a symbolic name of Jerusalem. Ariel (âr`ēəl), in astronomy, one of the moons, or natural satellites, of Uranus Uranus , in astronomy, 7th planet from the sun, at a mean distance of 1.78 billion mi (2.87 billion km), with an orbit lying between those of Saturn and Neptune; its period of revolution is slightly more than 84 years. ..... Click the link for more information. . Ariel (air -ee-ĕl) A satellite of Uranus, discovered in 1851 by William Lasell. Extensively imaged by Voyager 2 in 1986, Ariel has many craters and broad branching smooth-floored valleys such as Korrican Chasma and Kewpie Chasma. Its surface carries the scars of numerous impacts dating back to a time when the Solar System was still being formed. See Uranus' satellites ; Table 2, backmatter.

Ariel The Moons of Uranus | Exploring the Planets | National Air and Space Museum What's New The Moons of Uranus The image on the right is a composite of four images acquired by Voyager 2 in 1985 showing three moons of Uranus: Umbriel, lower left; Miranda, bottom right; Ariel, top right. At the time when this image was collected, only five moons of Uranus were known. Voyager 2 discovered 10 more moons in 1986, bringing the total to 15. Since then scientists using the Hubble Space Telescope and powerful Earth-based telescopes have continued to discover more moons orbiting Uranus. In 1997, two moons [Uranus XVI (Caliban) and XVII (Sycorax)] were discovered using the 200-inch Hale telescope at the Palomar Observatory in California, USA. In 1999, another three moons were discovered: one was discovered while comparing images from Voyager 2 and two more were discovered by astronomers using the Canada-France-Hawaii Telescope at Mauna Kea. As of 2014, 27 moons are known to orbit Uranus.

Uranian Satellites (in order by distance from planet) Name Kavalaars, Holman, Milisavljevic & Grav, 2001 22 km/14 mi Gladman, Holman, Kavelaars, Petit & Scholl, 1999 32 km/20 mi Nicholson, Gladman, Burns & Kavelaars, 1997 150 km/93 mi Gladman, Petie, Scholl, Kavelaars, Holman, 1999 50km/31 mi Kavelaars, Gladman, Holman, Petit & Scholl, 1999 48 km/30 mi Milisavljevic, Holman, Kavelaars & Grav, 2001 20 km/12 mi Uranus & Satellites Uranus and its five major moons are depicted in this montage of images acquired by the Voyager 2 spacecraft during its January 1986 flyby of the planet. The moons, counterclockwise from bottom right, are Ariel, Miranda, Titania, Oberon and Umbriel.

Miranda Miranda is the smallest of the five major satellites of Uranus, measuring just 480 kilometers (300 miles) in diameter. Voyager 2 passed between Miranda and Uranus during 1986, and returned this color composite of the moon. The carved dark streaks on the surface of this icy moon turned out to be ridges and valleys in higher resolution images. This high resolution image of Miranda was taken from a distance of 31,000 kilometers (19,000 miles), and shows a cratered surface broken by cliffs up to 20 kilometers (12 miles) high. Such fractures and grooves in the satellite's surface indicate a complex geologic history. Titania Titania is the largest satellite of Uranus. This image of Titania is a composite of 2 images taken by Voyager 2 on January 24, 1986. More Moons: Before the 1986 Voyager encounter, Uranus was known to have five moons. Those farthest from the planet have the highest density, and may consist of a silicate core covered by a thin, ice-rich crust. The moons show increasingly complex surface features closer to the planet.

Ariel The next moon out from Miranda, Ariel, is the brightest of the Uranian moons, and has the highest density (1.65 g/cm3). Umbriel Umbriel is the darkest of the Uranian moons, and has an icy crust pockmarked by craters. The surface is uniform in reflectivity, with the exception of a bright ring (top), which may be an impact crater. Oberon The outermost of the five major satellites, Oberon, appears much like the satellites. Oberon orbits Uranus at more than twice the distance of our own Moon from Earth. Puck Ten new moons of Uranus were discovered by Voyager in 1985 and 1986. Puck is only 150 kilometers (93 miles) across, and is the largest of the ten. These ten minor satellites all circle Uranus inside the orbit of Miranda. See this exhibition on display at the Independence Ave at 6th St, SW Washington, DC 20560 Satellites of the Outer Planets SATELLITES OF THE OUTER PLANETS The satellites of the giant outer planets are a surprisingly diverse group of bodies.

Most are composed of mixtures of water and other ices, including most likely ammonia ice, and rocky material. An amazing variety of unusual and spectacular geologic features are observed on these satellites, including active volcanism on two of them, which are illustrated on these pages. Also discussed are some of the processes that form them and the important issues they raise for geologists. Click on each image to view at full resolution or to access individual Web pages. A few of these images are stereo (three-dimensional) images, which are highlighted by the stereo symbol. Additional 3-D images of the satellites are available on the 3-D Tour of the Solar System . The Galilean Satellites The four large Galilean Satellites of Jupiter (from left to right in mosaic : Io , Europa , Ganymede , and Callisto ) resemble a miniature solar system. The global density, relative amount of rocky material, and duration and intensity of geologic activity on each satellite all decrease with increasing distance from Jupiter. Each satellite is very distinctive in appearance and geologic history. Io, the densest and innermost major satellite, is volcanically active today. Europa has a highly fractured, young icy outer shell.

Ganymede has a complex volcanic and tectonic history, and Callisto, the least dense and outermost satellite, is heavily cratered and rather bland by comparison. The geologic histories of these satellites are related to tidal deformation and heating, which is more intense closer to Jupiter. Titan The Uranian Satellites There are five major Uranian satellites (left to right in mosaic : Miranda, Ariel, Umbriel, Titania, and Oberon). They range from ~470 to 1600 kilometers across. They are composed of roughly equal mixtures of water and other ices and rocky material. Umbriel and Oberon are heavily cratered and Titania has a few large fractures. Miranda and Ariel have surprisingly complex geologic histories for such small bodies, the reasons for which are not well understood, but are probably related to tidal heating. At least 10 small satellites orbit near Uranus' thin ring system. Miranda & Ariel Neptune's Satellites Five small satellites orbit within or near the edge of Neptune's ring system . Further out, three major satellites orbit Neptune (left to right in mosaic : Proteus, Triton, and Nereid).

Nereid is in a distant retrograde orbit and is probably a captured asteroid. Neptune's largest satellite, Triton , is in a highly inclined retrograde orbit and is believed to have been captured by Neptune early in its history. Moons Moons: Moons are `fossils" into a planet's past.

The major, named moon systems are: Earth: Luna (The Moon) Mars: Deimos, Phobos Jupiter: Adrastea, Amalthea, Ananke, Callisto, Carme, Elara, Europa, Ganymede, Himalia, Io, Leda, Lysithea, Metis, Pasiphae, Sinope, Thebe Saturn: Atlas, Calypso, Dione, Enceladus, Epimetheus, Helene, Hyperion, Iapetus, Janus, Mimas, Pan, Pandora, Phoebe, Prometheus, Rhea, Telesto, Tethys, Titan Uranus: Ariel, Belinda, Bianca, Cordelia, Cressida, Desdemona, Juliet, Miranda, Oberon, Ophelia, Portia, Puck, Rosalind, Titania, Umbriel Neptune: Despina, Galatea, Larissa, Naiad, Nereid, Proteus, Thalassa, Triton Pluto: Charon (note: Pluto/Charon form a binary system, but Charon is the smaller so it is classed as the moon of Pluto) New, smaller moons are being discovered all the

 time with recent space missions.

The total count of moons (as of 12/18/2001) are: Mercury - 0 moons Mars - 2 moons Uranus - 20 moons Venus - 0 moons Jupiter - 28 moons Neptune - 8 moons Earth - 1 moon Saturn - 30 moons Pluto - 1 moon Moons range in shape from highly irregular to spheres. Their shape reflects their formation history, irregular objects are ill-formed moons (captured asteroids or comets) or pieces of a larger moon, spherical objects were once molten spheres, probably at the time of their formation. Moons of Mars: Deimos & Phobos We speculate, from their irregular appearances and low mean densities, that Deimos and Phobos, are captured asteroids. Both Deimos and Phobos are saturated with craters. Deimos has a smoother appearance caused by partial filling of some of its craters. Moons of Jupiter: Jupiter has 63 confirmed moons as of Jan 2009, i.e. moons with known orbits around Jupiter. Eight of these moons are regular, meaning they have prograde, nearly circular orbits.

They are composed of the four Galilean satellites, plus the inner or Amalthea group: Adrastea is a typical small moon Metis is the innermost known satellite of Jupiter Amalthea is one of Jupiter's smaller, irregular moons, an example of moon collecting dust from another moon (Io) The remaining 55 moons are irregular, they have a mixture of prograde and retrograde orbits with high inclinations and eccentricities. Jupiter's regular satellites are believed to have formed from a circumplanetary disk, a ring of accreting gas and solid debris analogous to a protoplanetary disk. The irregular satellites are substantially smaller objects with more distant and eccentric orbits. They form families with shared similarities in orbit (semi-major axis, inclination, eccentricity) and composition; it is believed that these are at least partially collisional families that were created when larger (but still small) parent bodies were shattered by impacts from asteroids captured by Jupiter's gravitational field. Moons of Saturn: The moons of Saturn are numerous and diverse, ranging from tiny moonlets less than 1 kilometer across to the enormous Titan, which is larger than the planet Mercury.

Saturn has sixty-two moons with confirmed orbits, fifty-three of which have names, and only thirteen of which have diameters larger than 50 kilometers. Saturn has seven moons that are large enough to become spherical. Twenty-four of Saturn's moons are regular satellites; they have prograde orbits not greatly inclined to the Saturn's equatorial plane. These include the seven major satellites, four small moons which exist in a Trojan orbit with larger moons, two mutually co-orbital moons and two moons which act as shepherds of Saturn's F Ring. Two other known regular satellites orbit within gaps in Saturn's rings. The relatively large Hyperion is locked in a resonance with Titan. The remaining regular moons orbit near the outer edge of the A Ring, within G Ring and between the major moons Mimas and Enceladus. The regular satellites are traditionally named after Titans and Titanesses or other figures associated with the mythological Saturn. The remaining thirty-eight, all small except one, are irregular satellites, whose orbits are much farther from Saturn, have high inclinations, and are mixed between prograde and retrograde. These moons are probably captured minor planets, or debris from the breakup of such bodies after they were captured, creating collisional families.

The irregular satellites have been classified by their orbital characteristics into the Inuit, Norse, and Gallic groups, and their names are chosen from the corresponding mythologies. The largest of the irregular moons is Phoebe, the ninth moon of Saturn, discovered at the end of the 19th century. The rings of Saturn are made up of objects ranging in size from microscopic to hundreds of meters, each of which is on its own orbit about the planet. Thus, a precise number of Saturnian moons cannot be given, as there is no objective boundary between the countless small anonymous objects that form Saturn's ring system and the larger objects that have been named as moons. At least 150 moonlets embedded in the rings have been detected by the disturbance they create in the surrounding ring material, though this is thought to be only a small sample of the total population of such objects. Daphnis drifts through the Keeler gap Atlas the second of Saturn's known satellites, orbits near the outer edge of the A-ring Enceladus is one of the innermost moons of Saturn.

Enceladus reflects almost 100 percent of the sunlight that strikes it and has evidence of internal heating and recent resurfacing effects Hyperion is one of the smaller moons of Saturn. It has a pock-marked body and is the largest irregularly shaped satellite ever observed.

Iapetus is one of the stranger moons of Saturn, its leading side is dark with a slight reddish color while its trailing side is bright Dione is the densest moon of Saturn other than Titan, and has several usual characteristics: 1) has a rocky core and ice crust, 2) is heavy cratering on trailing hemisphere, 3) has bright, wispy features Rhea is the largest airless satellite of Saturn that has different regions with different crater sizes indicating that parts of the moon have undergone resurfacing since formation Mimas is one of the innermost moons of Saturn with a very large impact crater that came close to fracturing the moon Tethys is an icy body similar in nature to Dione and Rhea Phoebe is the last of the known satellites of Saturn and orbits in a retrograde direction (opposite to the direction of the other satellites' orbits) in a plane much closer to the ecliptic than to Saturn's equatorial plane. Thus, Phoebe may be a captured asteroid with a composition unmodified since the time it was formed in the outer Solar System.

Moons of Uranus: Uranus, the seventh planet of the Solar System, has 27 known moons, all of which are named after characters from the works of William Shakespeare and Alexander Pope. William Herschel discovered the first two moons, Titania and Oberon, in 1787, and the other spherical moons were discovered in 1851 by William Lassell (Ariel and Umbriel) and in 1948 by Gerard Kuiper (Miranda). The remaining moons were discovered after 1985, either during the Voyager 2 flyby mission or with the aid of advanced Earth-based telescopes. A montage of Uranus' large moons and one smaller moon: from left to right Puck, Miranda, Ariel, Umbriel, Titania and Oberon. Uranian moons are divided into three groups: thirteen inner moons, five major moons, and nine irregular moons. The inner moons are small dark bodies that share common properties and origins with the planet's rings. The five major moons are massive enough to have achieved hydrostatic equilibrium (they were once molten spheres), and four of them show signs of internally driven processes such as canyon formation and volcanism on their surfaces.

The largest of these five, Titania, is 1,578 km in diameter and the eighth-largest moon in the Solar System, and about 20 times less massive than Earth's Moon. Uranus's irregular moons have elliptical and strongly inclined (mostly retrograde) orbits at great distances from the planet. Ariel is a relatively small satellite and is the brightest moon of Uranus Miranda with a jumbled surface unlike anything in the Solar System, indicates evidence of violent past with possible multiple shattering and reassembly Titania is the largest moon of Uranus and is marked by a few large impact basins Moons of Neptune: Neptune has thirteen known moons, by far the largest of which is Triton, discovered by William Lassell just 17 days after the discovery of Neptune itself. Over a century passed before the discovery of the second natural satellite, called Nereid. Neptune's moons are named for minor water deities in Greek mythology. Unique among all large planetary moons, Triton is an irregular satellite, as its orbit is retrograde to Neptune's rotation and inclined relative to the planet's equator.

The next-largest irregular satellite in the Solar System, Saturn's moon Phoebe, is only 0.03% Triton's mass. Triton is massive enough to have achieved hydrostatic equilibrium and to retain a thin atmosphere capable of forming clouds and hazes. Both its atmosphere and its surface are composed mainly of nitrogen with small amounts of methane and carbon monoxide. Triton's surface appears relatively young, and was probably modified by internally driven processes within the last few million years. The temperature at its surface is about 38K. Inward of Triton are six regular satellites, all of which have prograde orbits in planes that lie close to Neptune's equatorial plane. Some of these orbit among Neptune's rings. The largest of them is Proteus. Neptune also has six outer irregular satellites, including Nereid, whose orbits are much farther from Neptune, have high inclinations, and are mixed between prograde and retrograde. The two outermost ones, Psamathe and Neso, have the largest orbits of any natural satellites discovered in the Solar System to date.

Proteus is one of the darkest objects in the Solar System Ariels | Article about Ariels by The Free Dictionary Ariels | Article about Ariels by The Free Dictionary Also found in: Dictionary , Wikipedia . Related to Ariels: Aries Ariel (ā`rēĕl), in the Bible, aide of Ezra. In two other passages AV calls them "lionlike men" ("two ariels of Moab" in RV). Nothing is known of them. Ariel is also used as a symbolic name of Jerusalem. Ariel (âr`ēəl), in astronomy, one of the moons, or natural satellites, of Uranus Uranus , in astronomy, 7th planet from the sun, at a mean distance of 1.78 billion mi (2.87 billion km), with an orbit lying between those of Saturn and Neptune; its period of revolution is slightly more than 84 years. ..... Click the link for more information. . Ariel (air -ee-ĕl) A satellite of Uranus, discovered in 1851 by William Lasell.

Extensively imaged by Voyager 2 in 1986, Ariel has many craters and broad branching smooth-floored valleys such as Korrican Chasma and Kewpie Chasma. Its surface carries the scars of numerous impacts dating back to a time when the Solar System was still being formed. See Uranus' satellites ; Table 2, backmatter. Ariel

Question: Ariel is a satellite of which planet?
Answer: Uranus